package com.test.aqs;

import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicReference;

/**
 * 自旋锁
 * while循环 + compare 方法
 */
public class SpinLockDemo {
    //原子引用线程
    AtomicReference<Thread> atomicReference = new AtomicReference<>();

    public void myLock(){

        Thread thread = Thread.currentThread();
        System.out.println(Thread.currentThread().getName() + "\t come in ");
        while (!atomicReference.compareAndSet(null,thread)){

        }
    }

    public  void myUnlock(){
        Thread thread = Thread.currentThread();
        atomicReference.compareAndSet(thread,null);
        System.out.println(Thread.currentThread().getName() + "\t invoked myUnlock() ");
    }

    public static void main(String[] args) {

        SpinLockDemo spinLockDemo = new SpinLockDemo();
        new Thread(()->{
            spinLockDemo.myLock();
            try {
                TimeUnit.SECONDS.sleep(5);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            spinLockDemo.myUnlock();
        },"t1").start();

        try {
            TimeUnit.SECONDS.sleep(1);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        new Thread(()->{
            spinLockDemo.myLock();
            try {
                TimeUnit.SECONDS.sleep(1);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            spinLockDemo.myUnlock();
        },"t2").start();

    }
}
